The subject invention relates to a sealing member which is intended to be inserted in a well shaft and which consists of a hose which is mounted over a tube sleeve and has its ends sealed relative to the sleeve, and a pipe carrying pressurized water passing axially through said sleeve.
Prior-art sealing members of this kind include an air pipe which is connected to the space between the tube sleeve and the hose and which is intended to supply compressed air to that space. When compressed air is supplied to the space between the tube sleeve and the hose from a compressor, the hose is urged outwards into sealing abutment against the well shaft wall.